A charged particle beam device of a scanning electron microscope or the like is a suitable device in the measurement or observation of a pattern formed on a semiconductor wafer in which miniaturization is progressing. In the related art, PTL 1 discloses a stereo observation method as a method of obtaining three-dimensional information of a sample, and in particular, unevenness information of the sample, using a charged particle beam device.
The stereo observation method generates two images through irradiation of beams from two directions inclined with respect to the sample, performs stereo matching between the two images, calculates a height by determining corresponding points and obtains three-dimensional information.
PTL 2 proposes a technology performing dimension measurement of the pattern by irradiating a beam from an angle with respect to the pattern on the sample.
In PTL 3, unevenness information is obtained by determining whether a site on the sample corresponding to the one base portion to be a convex portion when one base portion having a peak of a profile formed by irradiating a beam converges loosely compared to another base portion or determining a site on the sample corresponding to the one base portion to be a concave portion when the one base portion converges steeply compared to the other base portion.